## Schemas for Python Data Frames

The Pandas data frame is probably the most popular tool used to model tabular data in Python. For in-memory data, Pandas serves a role that might normally fall to a relational database. Though, Pandas data frames are typically manipulated through methods, instead of with a relational query language. One can […]

## Solving for Hidden Data

Introduction Let’s continue along the lines discussed in Omitted Variable Effects in Logistic Regression. The issue is as follows. For logistic regression, omitted variables cause parameter estimation bias. This is true even for independent variables, which is not the case for more familiar linear regression. This is a known problem […]

## Detecting Data Differences Using the Sphering Transform

Many people who work with data are familiar with Principal Components Analysis (PCA): it’s a linear transformation technique that’s commonly used for dimension reduction, as well as for the orthogonalization of data prior to downstream modeling or analysis. In this article, we’ll talk about another PCA-style transformation: the sphering or […]

## More on Parameterized Jupyter

I’d like to share a great new feature in the wvpy package (available at PyPi). This package is useful in converting Jupiter notebooks to/from python, and also in rendering many parameterized notebooks. The idea is to make Jupyter notebook easier to use in production. The latest feature is an extension […]

## Short Data Science Video: Parameterized Juypter Notebooks

I am sharing a new short data science video: Parameterized Juypter Notebooks. It is an example from the wvpy package showing how to programmatically re-run the same notebook with many different inputs. If you are doing data science in Python, this may help you with your projects. link

## Data Algebra over Polars Ready for Production Use

The data algebra is a system for composing data manipulation tasks in Python. In the data algebra, operator pipelines (or even directed acyclic graphs) are the primary objects. Applying operations composes small data pipelines into larger ones. This allows the fluid specification, inspection, and sharing of data processing and data […]

## Experimenting with Polars for Data in Python

I’ve just started experimenting with the Polars data frame library in Python. I really like the programmable API it exposes. In fact I am starting an experimental adapter from the data algebra to Polars. When this is complete one can use the data algebra to run the same data transform […]

## What a Data Engineer Needs to Know About Bitemporal Modeling

A central data science engineering problem is how to organize general data into columns for analysis. I often refer to this as denormalization, or the deliberate arranging of data so all entries of a record are in a single row in a single table. In this note I will write […]

## An Effective Personal Jupyter Data Science Workflow

I would like to share what I have found to be a very effective personal Jupyter workflow for data science development. DALL-E “An Effective Personal Jupyter Data Science Workflow” Jupyter (nee IPython) workbooks are JSON documents that allow a data scientist to mix: code, markdown, results, images, and graphs. They […]

## Separating Code from Presentation in Jupyter Notebooks

One of the great conveniences of performing a data science style analysis using Jupyter is that Jupyter notebooks are literate containers that combine code, text, results, and graphs. This is also one of the pain points in working with Jupyter notebooks with partners or with source control. That is: Jupyter […]